[GFS2] Fix leak of gfs2_bufdata

This fixes a memory leak of struct gfs2_bufdata and also some
problems in the ordered write handling code. It needs a bit
more testing, but I believe that the reference counting of
ordered write buffers should now be correct.

This is aimed at fixing Red Hat bugzilla: #201028 and #201082

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

4 files changed, 6 insertions, 11 deletions

diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c
index af03bf380f46..04bceb75ff23 100644
--- a/fs/gfs2/lops.c
+++ b/fs/gfs2/lops.c
@@ -464,7 +464,7 @@ static void databuf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
         struct gfs2_inode *ip = GFS2_I(mapping->host);
 
         tr->tr_touched = 1;
-        if (!list_empty(&bd->bd_list_tr) &&
+        if (list_empty(&bd->bd_list_tr) &&
             (ip->i_di.di_flags & GFS2_DIF_JDATA)) {
                 tr->tr_num_buf++;
                 list_add(&bd->bd_list_tr, &tr->tr_list_buf);
@@ -473,7 +473,7 @@ static void databuf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le)
         }
         gfs2_trans_add_gl(bd->bd_gl);
         gfs2_log_lock(sdp);
-        if (!list_empty(&le->le_list)) {
+        if (list_empty(&le->le_list)) {
                 if (ip->i_di.di_flags & GFS2_DIF_JDATA)
                         sdp->sd_log_num_jdata++;
                 sdp->sd_log_num_databuf++;
@@ -640,10 +640,10 @@ static void databuf_lo_before_commit(struct gfs2_sbd *sdp)
                                  bd_le.le_list);
                 list_del(&bd1->bd_le.le_list);
                 sdp->sd_log_num_databuf--;
-
                 bh = bd1->bd_bh;
                 if (bh) {
                         bh->b_private = NULL;
+                        get_bh(bh);
                         gfs2_log_unlock(sdp);
                         wait_on_buffer(bh);
                         brelse(bh);
diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c
index 42dfd32059bc..502864b24196 100644
--- a/fs/gfs2/meta_io.c
+++ b/fs/gfs2/meta_io.c
@@ -464,7 +464,6 @@ void gfs2_attach_bufdata(struct gfs2_glock *gl, struct buffer_head *bh,
                 lops_init_le(&bd->bd_le, &gfs2_buf_lops);
         } else {
                 lops_init_le(&bd->bd_le, &gfs2_databuf_lops);
-                get_bh(bh);
         }
         bh->b_private = bd;
 
diff --git a/fs/gfs2/ops_address.c b/fs/gfs2/ops_address.c
index 45afd0508689..4c59cb110995 100644
--- a/fs/gfs2/ops_address.c
+++ b/fs/gfs2/ops_address.c
@@ -581,10 +581,8 @@ static void discard_buffer(struct gfs2_sbd *sdp, struct buffer_head *bh)
         if (bd) {
                 bd->bd_bh = NULL;
                 bh->b_private = NULL;
-                gfs2_log_unlock(sdp);
-                brelse(bh);
-        } else
-                gfs2_log_unlock(sdp);
+        }
+        gfs2_log_unlock(sdp);
 
         lock_buffer(bh);
         clear_buffer_dirty(bh);
@@ -598,7 +596,7 @@ static void discard_buffer(struct gfs2_sbd *sdp, struct buffer_head *bh)
 
 static void gfs2_invalidatepage(struct page *page, unsigned long offset)
 {
-        struct gfs2_sbd *sdp = page->mapping->host->i_sb->s_fs_info;
+        struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
         struct buffer_head *head, *bh, *next;
         unsigned int curr_off = 0;
 
diff --git a/fs/gfs2/ops_super.c b/fs/gfs2/ops_super.c
index 730c7228f6ad..2e392c994ab1 100644
--- a/fs/gfs2/ops_super.c
+++ b/fs/gfs2/ops_super.c
@@ -216,8 +216,6 @@ static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
         if (error)
                 return error;
 
-        memset(buf, 0, sizeof(struct kstatfs));
-
         buf->f_type = GFS2_MAGIC;
         buf->f_bsize = sdp->sd_sb.sb_bsize;
         buf->f_blocks = sc.sc_total;